1. Field of the Invention
This invention relates to a method of custom fitting a pair of eyeglass frames to the wearer's nose, and to the nosepiece formed in practice of such method. More particularly, the invention relates to a custom fitting technique for eyeglass frames in which an inexpensive wax wafer is heated and conformed to the wearer's nose and the frames to create a contoured pattern which can be sent to and processed by an eyeglass frames laboratory to form a permanent nosepiece which is precisely adapted to the wearer's nose and is finally aligned with the eyeglass frames while both the nosepiece and frames are in worn position.
2. Description of the Prior Art
A particular problem with prior art methods of fabricating an eyeglass frame is that it must be properly fitted to the wearer's nose to both ensure correct alignment of the eyeglass lens and to avoid discomfort caused by the necessarily small contact area between the nose and nose pad thereby causing discomfort to the wearer. Furthermore, the weight of the frames, if not properly supported by the nose pads, tends to cause the frames to slide down the wearer's nose, causing chafing and irritation resulting in considerable distress to the wearer.
Additionally, in normal use eyeglasses are repeatedly removed from and returned to their position of use with the frames placed against the nose and ears of the user. Unless the frames are returned to the same position each time, the lenses may well not be in proper position for optimal correction of vision. Erratic positioning of the frames when returned to use position will result in erratic correction with consequent decrease of sharpness and clarity of vision, frustrating the overall purpose and most important reason for wearing eyeglasses, i.e. proper eye sight correction.
Present day opticians and the like maintain a large inventory of eyeglass frames so that the wearer can select a particular style of frames and lenses. Since the frames must be properly fitted, the optician must normally carry a reasonably large selection of both styles and sizes to accommodate his customers. Additionally, it is desirable that opticians and the like be able to accurately conform the bridge portion of eyeglass frames to the wearer's facial features, and particularly the nasal structure, as quickly as possible by relatively low cost means, since the fit of the frames against the bridge of the nose is most critical for the wearer's comfort as well as proper vision correction.
Of particular interest with respect to fitted devices for holding eyeglass frames on the wearer's nose is U.S. Pat. No. 3,701,592 to Fernandez. This patent discloses a pair of spectacles provided with a nose bridge specifically contoured to conform to the upper portion of the nose of the wearer. A central portion of the bridge is made from a plastic or metal material and includes a U-shaped cavity which forms a vacuum around a portion of the nose for retaining the spectacles in their proper position. An impression of the upper nose is formed from a moldable compound applied to the inner surface of a fixture. Dental stone, in its pliable state, is then molded with the impression form, and, after setting, forms a replica of the nose. A two-part die is created incorporating the shape of the nose replica, and an internal cavity is filled with a settable plastic to form a vacuum holder piece. A particular disadvantage of the vacuum spectacle bridge taught by Fernandez is that it requires a rather large holder which extends a significant distance along both the length and width of the wearer's nose thereby detracting from the esthetic appearance of the spectacles. Additionally, the nosepiece must be initially deformed when the spectacles are positioned on the wearer's nose in order to exhaust the air from the vacuum retaining means so that the vacuum bond can be formed. Furthermore, in use, the application of suction to the nose over a prolonged period has a tendency to turn the contacted area of the nose red and to irritate the wearer's skin.
Also of interest in U.S. Pat. No. 3,043,191 to Lanski which discloses a method of fitting spectacle frames to spectacle pads. The method disclosed by the Lanski patent involves a positioning of a blank member having a pair of interconnected pads on the bridge of the wearer's nose. The blank member is formed from a moldable material, softened by heating in water, which is then formed to the shape of the nasal structure. Adhesive is then used to attach the pads to the frames of the eyeglasses.
Another method of fitting eyeglass frames with a moldable material is disclosed in U.S. Pat. No. 3,597,053, to Massman. This patent describes spectacle frames having a nose portion and a pair of temples, both of which have surfaces for enhancing the engagement between the nose and temple and ear portions of the head. The pliable material may be of the type which is either in a liquid state at ambient temperature or is a heat responsive thermoplastic substance such that it becomes malleable at temperatures slightly above ambient temperature. In FIGS. 7 and 8, an inverted U-shaped bridge segment is illustrated which is heated for softening of the thermoplastic material. In this pliable state the nosepiece is urged against the nose of the wearer causing it to conform to the contacted surface of the nose.
Also of general interest are the following U.S. Pat. Nos.:
______________________________________ Fensky 1,611,428 Montalov-Guenard 2,234,729 Nerney 2,308,200 Moeller 2,582,345 Baldanza 2,682,196 Hoffmaster 3,189,913 Angelis 3,233,956 Gordon 3,345,737 Fartenberry 3,476,468 Olson 3,584,939 ______________________________________